1. Field of the Invention
The present invention relates to apparatus for uniformly spreading a coating on a surface, and more specifically to a paint roller adapted to apply paint simultaneously to two perpendicular, intersecting environmental surfaces being painted. It is contemplated that manual painting in commercial, residential, institutional, and industrial facilities will provide the most widespread application of the invention. However, any task requiring that a viscous fluid be applied as a coating to an environmental surface having intersecting, non-parallel surfaces will benefit from the invention.
2. Description of the Prior Art
Paint rollers have gained wide acceptance as the implement of choice for spreading a coating on many flat surfaces. Coatings such as paint, stain, varnish, sealer, waterproofing and the like may be readily applied with a roller to horizontal and vertical surfaces by essentially untrained operators with generally acceptable results. A wide variety of paint rollers assemblies are currently available, the xe2x80x9cstandardxe2x80x9d roller including a replaceable roller cover, a barrel or cage portion for supporting the roller cover, and a frame with a handle. Roller covers are available in a wide variety of naps designed for painting a variety of surface textures ranging from smooth (such as finished plaster) to extremely rough surfaces, such as stucco. When a conventional paint roller is used in a corner (i.e., where two perpendicular surfaces meet), one of two outcomes is desired. Sometimes, it is desirable to prevent the coating being applied to one of the surfaces from contacting the adjoining, intersecting surface. More often however, the coating being applied will be continued from the first surface onto the second surface. Traditional paint rollers exhibit notoriously poor performance in corners, often necessitating the painter xe2x80x9ccutting inxe2x80x9d the corners with a conventional paint brush or similar tool. xe2x80x9cCutting inxe2x80x9d is an informal term for correcting unsatisfactory results by an alternative manual painting method.
U.S. Pat. No. 4,402,102, for CORNER PAINT ROLLER; issued Sep. 6, 1983, to Ziad A. Al-samman, teaches a corner-painting assembly attachable to the end of a conventional paint roller. The end surface of the Al-samman apparatus may be either bristle-like to simulate a paint brush, or may be of the same material and textures as the outer surface of the roller cover. The end cap apparatus is fastened to the roller core by prongs specifically adapted to interact with wire members forming the core of the paint roller frame. The junction between the edge of the roller cover and the insertable end cap is uncontrolled and in use, a nonuniform deposition of coating on at least one the two perpendicular surfaces often results. In contradistinction, the inventive paint roller end cap apparatus is designed for retention in the end of a conventional paint roller cover by at least one prong adapted to fit between the inner diameter of the roller cover and the outer diameter of the barrel or cage. This means that the inventive end cap may be applied universally to any paint roller, not just to one specific brand or design as is the case with the Al-samman apparatus. The prong occupies only a limited portion of the circular cap, whereas Al-sammam has corresponding structure having a plurality of prongs located periodically along a entire circular path on the base. It should be noted that installing the cap of Al-sammam may not be readily accomplished since it is difficult to assure that each prong is appropriately aligned for insertion. By contrast, the prong in the present invention does not engage any specific element of the roller, which makes it easy to align for insertion. The prong in the present invention has configuration different from any of those of Al-sammam. In addition, texture of the coating applicator surface of the inventive end cap is carefully formed to abut the edge of the roller cover so that in use, a smooth, continuous coating can be applied to both intersecting surfaces.
Another U.S. Pat. No. 5,584,092 for ROLLER HAVING SLIP-ON CAGE FOR PAINT ROLLER COVER; issued Dec. 17, 1996, to Bruce C. Polzin, et al., describes a one-piece roller assembly which is closed at one end, and terminates in a rounded tip portion at the opposite end. The Polzin, et al. system necessitates the use of two different roller assemblies for coating jobs where both a xe2x80x9ccontinue around a cornerxe2x80x9d and also a xe2x80x9cstop at the cornerxe2x80x9d mode of operation are required. Either two roller covers must be cleaned and the paint remaining in the covers at the end of the job wasted, or both roller covers must be discarded. The inventive end cap system, on the other hand, requires the cleaning or discarding of only a single roller cover. The inventive end cap may be installed or removed as required throughout the coating job. The minuscule amount of paint remaining in the paint holding medium of the inventive end cap presents a trivial clean up job and only a small amount of the coating material remains in the paint holding medium of the end piece. The inventive system also produces a uniform deposition of coating material on both surface proximate the corner while the Polzin, et al. cover may not deposit coating material uniformly near the corner because of its nonconforming, conical contour. Polzin et al. lacks the end cap bearing bristles on the end of the cylinder, wherein the end cap has a single attaching prong. The present invention has these features.
U.S. Pat. No. 5,613,264 for PAINT ROLLER CORNER COVER; issued Mar. 25, 1997, to Curtis N. Knowles, teaches another insertable end cap for corner painting. The Knowles apparatus lacks the controlled edge contour of the inventive end cap, resulting in coating non-uniformity when used in a corner. The Knowles design uses an annular flange for insertion into the open end of a paint roller with a series of integrally molded, circumferentially spaced lugs protruding from the flange for engagement with the inside of the roller cover. A significant difference between Knowles and the present invention is that whereas the annular flange forms a full circle, the present invention utilizes a corresponding member which extends along only a limited portion of a circle. Also, thickness of the Knowles apparatus may preclude its use with some paint roller barrels. Also, the protruding lugs may tear the inner surface of the paint roller cover, particularly if the Knowles end cap is inserted after moisture has accumulated inside the roller cover either from the coating being applied or from a previous cleaning of the roller cover. The inventive end cap overcomes these disadvantages by presenting a thin apparatus able to adapt to a wide variety of paint roller barrel lengths or differences in lengths of paint roller covers. The prong of the inventive end cap slide easily into the end of a paint roller without any damage to a damp roller cover, and is configured differently from any structure of Knowles.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
The present invention features a universal end cap attachment for a paint roller. The inventive end cap is designed so that textured, paint retaining material on the outer surface of the end cap abuts and conforms to the textured, paint retaining material of the paint roller cover, thereby forming a corner arrangement that will uniformly spread coating material on two intersecting surfaces such as in corners. The end cap is designed for frictional engagement between the inner surface of the paint roller cover and the outer surface for the barrel or cage of the paint roller frame by means of at least one prong situated within not more than a continuous 180xc2x0 of the perimeter of the end cap. The design of the prong is such that damage to the cardboard core of the paint roller cover is minimized, even if the paint roller cover is wet from being cleaned or from absorption of the coating material being applied. The end cap may be readily inserted and removed during the coating job as required and, in addition, is easily cleanable.
Provision of at least one prong situated within not more than a continuous 180xc2x0 of the perimeter of the end cap eliminates the problem of alignment of prongs confronting designs having many prongs. At least one prong situated within a not more than a continuous 180xc2x0 of the perimeter of the end cap is readily inserted between the roller cover and the cage regardless of minor variations in clearances which occur due to manufacturing tolerances. This arrangement accounts for only a limited portion of the circumference of the circular portion of the roller into which it is inserted. The prong is curved at its distal end wherein it engages the roller cover, and is straight at its proximal end wherein it is anchored to the base of the novel end cap. This configuration assists in retaining the prong in engagement with its associated roller assembly.
It is therefor an object of the invention to provide an end cap attachment for a standard paint roller to facilitate the application of coatings to intersecting surfaces and corners.
Another object of the invention is to require only one prong for engaging the a roller frame and roller cover, although more than one prong can be utilized.
A further object of the invention is to compensate for variations in clearance between a roller cover and cage of the roller when inserting a prong of a cap there between.
An additional object of the invention is to configure the prong to be maximally effective in engaging the roller frame and roller cover.
It is a further object of the invention to provide an easily installable and removable attachment which may be used with any commercially available roller frame and roller cover combination.
It is yet another object of the invention to provide an attachment which, in use, spreads a coating uniformly on both intersecting surfaces leaving no visible lines or other defects in the coating on either surface.
It is yet a further object of the invention to provide an attachment for a paint roller which is inexpensive to manufacture.
It is a still further object of the invention to also provide an end cap attachment for a paint roller which is easy to clean.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.